[PATCH v6 1/2] tracing: Include PPIN in mce_record tracepoint

From: Avadhut Naik
Date: Mon Apr 01 2024 - 13:15:29 EST


Machine Check Error information from struct mce is exported to userspace
through the mce_record tracepoint.

Currently, however, the PPIN (Protected Processor Inventory Number) field
of struct mce is not exported through the tracepoint.

Export PPIN through the tracepoint as it provides a unique identifier for
the system (or socket in case of multi-socket systems) on which the MCE
has been received.

Also, add a comment explaining the kind of information that can be and
should be added to the tracepoint.

Signed-off-by: Avadhut Naik <avadhut.naik@xxxxxxx>
Reviewed-by: Sohil Mehta <sohil.mehta@xxxxxxxxx>
Reviewed-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
---
include/trace/events/mce.h | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/include/trace/events/mce.h b/include/trace/events/mce.h
index 9c4e12163996..294fccc329c1 100644
--- a/include/trace/events/mce.h
+++ b/include/trace/events/mce.h
@@ -9,6 +9,14 @@
#include <linux/tracepoint.h>
#include <asm/mce.h>

+/*
+ * MCE Event Record.
+ *
+ * Only very relevant and transient information which cannot be
+ * gathered from a system by any other means or which can only be
+ * acquired arduously should be added to this record.
+ */
+
TRACE_EVENT(mce_record,

TP_PROTO(struct mce *m),
@@ -25,6 +33,7 @@ TRACE_EVENT(mce_record,
__field( u64, ipid )
__field( u64, ip )
__field( u64, tsc )
+ __field( u64, ppin )
__field( u64, walltime )
__field( u32, cpu )
__field( u32, cpuid )
@@ -45,6 +54,7 @@ TRACE_EVENT(mce_record,
__entry->ipid = m->ipid;
__entry->ip = m->ip;
__entry->tsc = m->tsc;
+ __entry->ppin = m->ppin;
__entry->walltime = m->time;
__entry->cpu = m->extcpu;
__entry->cpuid = m->cpuid;
@@ -55,7 +65,7 @@ TRACE_EVENT(mce_record,
__entry->cpuvendor = m->cpuvendor;
),

- TP_printk("CPU: %d, MCGc/s: %llx/%llx, MC%d: %016Lx, IPID: %016Lx, ADDR: %016Lx, MISC: %016Lx, SYND: %016Lx, RIP: %02x:<%016Lx>, TSC: %llx, vendor: %u, CPUID: %x, time: %llu, socket: %u, APIC: %x",
+ TP_printk("CPU: %d, MCGc/s: %llx/%llx, MC%d: %016Lx, IPID: %016Lx, ADDR: %016Lx, MISC: %016Lx, SYND: %016Lx, RIP: %02x:<%016Lx>, TSC: %llx, PPIN: %llx, vendor: %u, CPUID: %x, time: %llu, socket: %u, APIC: %x",
__entry->cpu,
__entry->mcgcap, __entry->mcgstatus,
__entry->bank, __entry->status,
@@ -65,6 +75,7 @@ TRACE_EVENT(mce_record,
__entry->synd,
__entry->cs, __entry->ip,
__entry->tsc,
+ __entry->ppin,
__entry->cpuvendor,
__entry->cpuid,
__entry->walltime,
--
2.34.1